There is increasing interest in implementing electrical power networks by connecting power generators at various positions around the network to create a distributed generation system. This provides a number of advantages, but has the disadvantage of increasing the fault level of the network. This may result in allowable limits for equipment within the network being eventually exceeded, or requiring cables, switchgear and associated protection hardware to be upgraded to increase the allowable limits to accommodate the increased fault levels. This may be expensive or, in the case of an established network, unacceptable for other reasons.